 A unit's Experience will usually be added to combat attack, or defence values.
 Experience can also affect other aspects of the game. Submarine Evasion/Detction, etc.
 After Turn #1 new units usually are placed on the map with a Negative Experience rating.
 Units with Experience below 0 gain 50 points per turn.
 Units above 0 experience gain 1 or 2 points per turn. 
 ' new units vary....see code below. Example: Fighter, Tac, and Level Bombers start at -600 Experience. It will take 12 turns for them to be
   trained. (50 points per turn for 12 turns) -600 to 0 Experience. 
 Infantry hit Zero in just 4 turns. (Longer for specialized Infantry like Para, Engineer, etc.)
Some of these values may get tweaked over the years, but this is the general concept's description.
 
 If XPOpt = 1 Then ' new unit exp penalty (onoy if using the option)
    If Turn > 1 Then ' first turn are old units trained
    If Units(u, 15) > 1 Then ' not applicable to mines, airstrips, special marker stuff
    If Units(u, 9) <> PartisanRecN Then ' not partisans !!! (they suck already)
        Select Case Units(u, 31)
        Case 7 ' forts
           Units(u, 10) = Units(u, 10) - 100 ' New forts begin with -100 Experience
        Case 0 ' inf
           Units(u, 10) = Units(u, 10) - 200 '
           If Units(u, 61) > 0 Then Units(u, 10) = Units(u, 10) - 100 ' eng
           'If Units(u, 62) > 0 Then Units(u, 10) = Units(u, 10) - 100 ' engineer
           If Units(u, 42) > 0 Then Units(u, 10) = Units(u, 10) - (Units(u, 42) * 50) ' initiative
           If Units(u, 47) > 3 Then Units(u, 10) = Units(u, 10) - 100 ' cavalry takes longer to train
           If Units(u, 60) = 3 Then Units(u, 10) = Units(u, 10) - 100 ' para ability
        Case 1, 2, 3, 5 ' tank, recon, at, AA
           Units(u, 10) = Units(u, 10) - 300 '
        Case 8, 9, 10 ' ftr, tac, sac
           Units(u, 10) = Units(u, 10) - 600
        Case 11 ' subs
           Units(u, 10) = -100
        Case 12 ' light capital ships
           Units(u, 10) = -300
        Case 13 ' heavy capital ships
           Units(u, 10) = -600
        Case 14 ' CV's
           Units(u, 10) = -300
        Case Else ' else
           Units(u, 10) = Units(u, 10) - 400
        End Select
    End If
    End If
    End If
    End If